Cross over games are dangerous for a dev though, they have a chance to damage two franchises, and those two are so valuable I'm not sure would bethesda take the chance on it.

Grand Theft Sheep :D

An mmorpg or open world rpg with animals as characters

Might and Magic VI/VII game (or sequel) with modern graphics, effects, hi-res textures etc
Zelda-like game in Might and Magic universe
Traditional Pokemon series game for home console with jaw dropping visuals

If that was a launch game, I'd buy NX Day 1.

@OP

I'd love a remake or another sequel to Thrillville.  Those games were awesome.  I always wanted full-fledged remakes of some more obscure titles I had fun with, like Kingsley's Adventure, Crusaders of Might and Magic, or the King's Field games. 

As for a game I thought of, I always thought it would be kind of neat to make a game that was open world and had a country area, a suburban area, and a big city to explore.  You could go into almost any building, if it wasn't illegal to enter them, otherwise you would have to break in.  You could get a job, build/buy your own car, and start a family.  The kicker was, there was little to no story.  You make your own story.  You could be an upstanding citizen, working a job, dating and maybe even raise a family OR be not such an upstanding citizen.  Maybe that just means being rude to people, but you could also be a criminal.  Either a petty thief, a gang member/leader, or even a serial killer.  The AI would have to be pretty good, though, cause if you got stupid, then first the local cops would be on you, but then also the state police, and finally the feds.

Funny you should say that, because I was contemplating whether or not to mention a Sim City 5. I have Cities Skylines, and surprisingly it is a godsend in the way that it's finally, after a decade of nothing good, something that deserves to stand next to SimCity 3000 and SimCity 4. I love the free-form building, you can basically make whatever city you want. Free layout of roads, making the most epic highway interchanges, that's basically perfect. That part of the game is genius, but besides that somehow it is still not truly the thing I dreamed about though. The old SimCities up to 4 had nuances that made the games feel they had just that much more depth and realism (probably not the perfect word), feel 'grander' or a larger scale, more challenging and in turn more addicting to play. It's hard to explain.

And maybe I'm still being unfair, for one because Cities Skylines is probably as close as it's going to get and because I'm also not mentioning a Rollercoaster Tycoon 4 (I know there technically is one, but you know, a real one). I figured by the looks of things Planet Coaster is actually going to be what I ever wanted out of a Rollercoaster game, if it's going to get the content and features I think and hope it is. Maybe though, I'll end up feeling similar about this game than I do about Cities Skylines; great game, but it isn't "it". It's weird I know.

But yeah anyway, Cities Skylines is great, and as a sidenote I would also very much take your Age of Empires 4!

That is a good one!

Animal Crossing MMO that transcends generations. With massive updates and not just cosmetics.

You had GTA london that's enough don't get greedy.

Make it a sequel to ring of red instead and I'm in especially if they let you upgrade the ground troop's.